In a method for preparing a color proof by using a silver halide color photographic light-sensitive material having a white support, a plural number of different black-and-white halftone images obtained by color separation and halftone image conversion from a colored original are printed in sequence on a single color photographic paper in the contact printing manner, and the printed photographic paper is subjected to color-development to get the couplers contained therein to produce imagewise dyes to thereby form a color image for use as a color proof.
In the above technique, however, when on the color proof a color image is formed so as to get closely akin to the color image of the original, the black image density on the color proof lacks as compared to the original's, whereas when the proof's black image density is made so as to have a close resemblance to the original's, the proof's resemblance to the color image of the original is deteriorated, and thus it is very difficult to satisfy the reproductions of both at the same time.
As a means to solve the above disadvantage there is known a technique to provide besides the yellow, magenta and cyan color forming layers a fourth black layer different in the spectral sensitivity from any of the three layers; for example, Japanese Patent Publication Open to Public Inspection (hereinafter abbreviated to JP O.P.I.) No. 122637/1991 discloses a technique to use four different image-forming layers: yellow, magenta, cyan and black image-forming layers. JP O.P.I. Nos. 289846/1990 and 183251/1990 also disclose techniques for improving the above problem. These techniques, however, have such shortcomings that they have need of increasing the number of exposures, resulting in a loss of productivity, or lack the image stability, and therefore, they need further improvements in order to be provided for practical use.
JP O.P.I. No. 100352/1993 discloses a technique to use a silver halide emulsion (hereinafter referred to as a pan chromatic emulsion) having a spectral sensitivity covering all the respective yellow, magenta and cyan image-forming layers. This method must enable the obtaining of the same color densities and quality vividness as the original because color densities can be set so as to be closely akin to that of the original and the panchromatic emulsion can make up for the shortage of blackness formation. However, the actual introduction of the panchromatic emulsion to the light-sensitive material has the disadvantage that it causes the yellow, magenta, cyan and black image densities to become liable to largely change according to fluctuation in the exposure amount, and therefore it needs further improvement.
As a result of our continued investigation, we have now reached the following idea: since it is difficult for both green-sensitive and red-sensitive emulsions to eliminate the blue-sensitivity peculiar to silver halide therefrom, any practical light-sensitive material comprises a blue-sensitive layer as the top layer, a yellow filter layer as an interlayer, and other color-sensitive layers provided thereunderneath. Incidentally, regarding the panchromatic emulsion in a light-sensitive material for use as a color proof, it is expected that its exposed part do not form any color, but its part unexposed to any of blue, green or red light at all alone contribute to black formation, so that particularly where the panchromatic emulsion is incorporated in a layer underneath the yellow filter layer, the decoloration of the panchromatic emulsion due to its exposure to blue light does not function as was set up, and as a result, the formed color density largely varies according to fluctuation in the exposure condition.
Upon this, if the yellow filter should be eliminated, then the earlier-mentioned spectral sensitivity separation becomes impossible.
Accordingly, in order to let the panchromatic emulsion function and to make the spectral sensitivity separation by eliminating the yellow filter layer or reducing the function of the filter layer, we, the inventors, have accomplished the optimization of the respective emulsion layers' sensitivities to blue light, and thus we have made the present invention.